Well, despite using THERMAL paste with INSULATED wallpaper, various mini dehumidifiers including a special Lakeland coat hanger that catches water in crystals, opening the bedroom window in the day slightly and having an electric dehumidifier and air filter that has some airflow this mold persists! I cannot understand when doing all the right things why this is happening as it defied physics. The house is Victorian with no cavity but this shouldn't be an issue as other rooms in the house I have treated have been ok up to now. Would a second layer of the insulated paper be enough to stop this, and it would get rid of the forming mold as the paste is meant to kill it on contact ? Otherwise its a pain in the backside. We don't have the central heating on (can't afford it) except 5 mins here and there as we have a log burner. Even the wooden doors to this cupboard we had stripped of paint 26 years ago still attract moisture! I even sprayed one of the walls with mold blocker which hasn't prevented it coming back.
Unstoppable Mold
- Thread starter DIY67
- Start date
Inadequate ventilation and poor lifestyle choices .
It may be a combination of cold temperatures (you mention no CH) and high humidity. What sort of dehumidifier do you use, if its a compressor they are useless below about 15C (I have two so that's enough to know), you may need a desiccant although they are about half the efficiency (yes I have one of those too).
Where is this mold (you don't seem to say) is it in an unheated room ? Surely not the room with the woodburner ?
Is the woodburner fully enclosed ? Are you storing wood inside the house, this could be a source of moisture, is it kiln dried or picked up from the roadside ?
Where is this mold (you don't seem to say) is it in an unheated room ? Surely not the room with the woodburner ?
Is the woodburner fully enclosed ? Are you storing wood inside the house, this could be a source of moisture, is it kiln dried or picked up from the roadside ?
Your wall is saturated and cold which creates condensation mould. Insulated wall paper won’t make a difference. Build a stud wall/ walls and create a gap so cold and damp isn’t transferred from the walls. Keep the room warm thereafter
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Yr Wyddgrug has been around for a long time, English name Mold, being in a valley it does get wet, and the Alyn does flood from time to time.
But assuming just spelt wrong, and you meant to say mould, start point is what temperature and humidity reading. My house
with the relative humidity it compares how much water is in the air, compared to how much water it could hold, so at the temperature goes up the relative humidity goes down, at zero°C it can't hold any moisture, so the temperature of the walls and windows matter. But also wiping the walls with something to kill the mould also helps.
The utility room, unheated at 11.1°C as one would expect, is the worst room, at 63% on the windowsill. The flat under main house, also has heating set low at 17.2°C and 39%, my bedroom 18.1°C at 40%, and the living room 20.1°C at 36% are typical, I look today and about the same as picture taken 16th January.
I think in general mould has got worse, as I, for one, do not heat rooms not in use, but the shower I blame for most of the mould, and where the extractor fan is placed and when it is run.
My shower door seals on the bottom of the shower tray, so there is no chimney effect, I do not run an extractor while having a shower, all that does is drag the moisture out of the shower area, once the shower is completed then is the time to run the extractor, but also where does it drag the replacement air from?
Even when snowing, air from outside has very little moisture in it, it is too cold, we are looking at the dew point, so at 20.1°C at 36% how cool will it need to be to release the moisture. This calculator tells me the air needs to cool to 4.58°C to release the moisture in the air. So as long as my windows and walls are over 4.58°C they will not get damp.
Best room is my bedroom needs to cool to 3.14°C before it hits the dew point.
So last house, the bathroom got replacement air from inside the house, and the bathroom was cold, so it never dried out, so the only real option is a heat recovery unit, so one is taking dry cold air from outside, and heating it with the damp warm air from inside.
But assuming just spelt wrong, and you meant to say mould, start point is what temperature and humidity reading. My house
with the relative humidity it compares how much water is in the air, compared to how much water it could hold, so at the temperature goes up the relative humidity goes down, at zero°C it can't hold any moisture, so the temperature of the walls and windows matter. But also wiping the walls with something to kill the mould also helps.The utility room, unheated at 11.1°C as one would expect, is the worst room, at 63% on the windowsill. The flat under main house, also has heating set low at 17.2°C and 39%, my bedroom 18.1°C at 40%, and the living room 20.1°C at 36% are typical, I look today and about the same as picture taken 16th January.
I think in general mould has got worse, as I, for one, do not heat rooms not in use, but the shower I blame for most of the mould, and where the extractor fan is placed and when it is run.
My shower door seals on the bottom of the shower tray, so there is no chimney effect, I do not run an extractor while having a shower, all that does is drag the moisture out of the shower area, once the shower is completed then is the time to run the extractor, but also where does it drag the replacement air from?
Even when snowing, air from outside has very little moisture in it, it is too cold, we are looking at the dew point, so at 20.1°C at 36% how cool will it need to be to release the moisture. This calculator tells me the air needs to cool to 4.58°C to release the moisture in the air. So as long as my windows and walls are over 4.58°C they will not get damp.
Best room is my bedroom needs to cool to 3.14°C before it hits the dew point.
So last house, the bathroom got replacement air from inside the house, and the bathroom was cold, so it never dried out, so the only real option is a heat recovery unit, so one is taking dry cold air from outside, and heating it with the damp warm air from inside.
All rooms are well into the 70s in moisture here as even running the dehumidifier to get down the at bes the mid 50s doesn't last long until it goes up again. If the humidity outside is high its impossible to stop it affecting household moisture, even with double glazing. I don't know how you do it.
Dehumidifiers, draw moisture out of the air quite slowly, your shower/bath, puts moisture in the air in massive amounts, quickly. Opening a window afterwards is just too late, the moisture will have condensed out onto surfaces by them. You need to have an effective extract fan, drawing the moist air straight out, as just as fast as it is created. In addition, it needs to be automatic (PIR), so it cannot be forgotten to turn it on, when the shower/bath is in use, plus continuing to run for around 20 minutes, after the room is vacated.
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